Nozzle closure



March 20, 1962 B- B. FOWLER 3,026,047

NOZZLE CLOSURE Filed Jan. 12, 1959 INVENT OR.

BLAIR B. FOWLER JMYQT AT'roRug United States ate-n t O 3,026,047 NOZZLE CLOSURE Blair B. Fowler, Monrovia, Caiii, assignor to Aerog'ete grgneral Corporation, Azusa, Califi, a corporation of Filed Jan. 12, 95?, Ser. No. 786,347 8 flaims. (Cl. 239-409) The present invention relates to nozzle closures for flame throwers. In such equipment a pressurized stream of fuel is ejected from a fuel tank and through a flame cone in which a flame is maintained to cause burning of the issuing fuel stream while the flame thrower is in operation, while the equipment is not in operation means must be provided to prevent loss of liquid from the fuel tank and should also be provided to prevent entry of foreign objects into the flame cone.

In the flame thrower described in copending United States patent application Serial No. 786,350 filed January 12, 1959, a single shot flame thrower of light weight and simple construction is disclosed in which the trigger serves only to effect pressurization of the liquid fuel tank and ignition of the issuing stream of fuel, and since this single shot flame thrower is designed to be carried and fired in any position it is necessary to provide a nozzle enclosure that will be positively liquid tight until the flame thrower is fired.

In addition the flame thrower described in the coperiding patent application above referred to is provided with a flame cone having its forward opening aligned with an opening in a shroud covering the forward end of the flame thrower, the forward edge of the flame cone being spaced from the edge of the opening in the shroud to provide an annular opening through which air can flow to enter the cone at the rear thereof to maintain combustion of the flame in said co'ne, since the annular opening should be kept closed against entry of debris until the flame thrower is put into use a closure for the opening also should be provided. 7

It is an object of the invention to provide a fuel nozzle closure clamped in liquid tight position on the nozzle of a flame thrower and automatically ejected from its position on releasing pressurized fuel into said nozzle.

Another object of the invention is to provide closure means for an opening aligned with the nozzle in a shroud covering the nozzle, the shroud opening closure being ejected by the ejection of the nozzle closure.

With the above and other features and objects in View as will appear from the following specification, the invention comprises a nozzle closure for a flame thrower covering all openings in said nozzle until the flame thrower is put into use, means holding said closure in position until pressurized fuel is admitted to said nozzle, whereupon a weakened peripheral portion of the nozzle closure will be ruptured, said nozzle closure being thereby freed from the holding means and the portion thereof adapted to cover said openings ejected out of the shroud. The invention further comprises closure means for the opening in the shroud aligned with the nozzle, said shroud closure means being ejected from said opening by the ejected portion of the nozzle closure.

In the drawings:

FIG. 1 is a longitudinal central section through the nozzle end of a flame thrower and shroud enclosure with closures for the nozzle and shroud opening aligned with the nozzle in operative position.

FIG. 2 is a view similar to FIG. 1 but showing both closures being expelled through the shroud opening by the pressurized rod-like stream of fuel ejected when the flame thrower is in operation.

Referring now to FIG. 1 the numeral 10 indicates the nozzle of the flame thrower which is provided with a main central bore 11 through which fuel is projected in a rod-like stream, when a fuel tank, not shown, is placed under pressure, to a distance in excess of 50 yards in the case of a specific design of flame thrower in which these parts are used, and when using thickened fuel with a pressure in the tank of about 250 lbs. per sq. in.

The nozzle is also provided with a passage 12 through wmch a fine stream of fuel bled from the tank is sprayed through a lateral orifice 13 near the end of the nozzle into a conical flame cone 14 surrounding and housing the nozzle and axially aligned therewith. This bled-01f fuel is ignited by suitable means to provide a flame whirling around the base of the fuel-rod issuing from the nozzle when the flame thrower is in operation and ignites the peripheral surface of the fuel-rod.

To prevent loss of fuel before the flame thrower is put to use both through the main bore 11 and bleed passage 12, a cap 15 of frangible material is securely held on the nozzle 1i} and is made to fit over the end of the nozzle by inner flat surface 16 at the forward end of the nozzle and over the lateral orifice 13 by the inner surface of the body of the cap. The cap 15 is held in position by the engagement of an outwardly turned peripheral flange 17 at the open end of the cap with an interior flange 18 on a threaded ring 19 which is screwed onto a threaded shoulder 26 on the nozzle. The ring 19 is provided with a tubular portion or skirt 1% overlying the cap and acting to guide the cap in its forward movement off the nozzle;

The nozzle 10 is provided with an exterior peripheral groove 1 rearwardly of the lateral orifice 12a and an 0 ring 22 seal is seated in the recess to provide a leak proof seal between the outer surface of the nozzle and the inner surface of cap 15.

The cap is provided with a peripheral groove 15a in its wall located rearwardly of the engagement of O ring 22 with the cap, the thickness of the Wall of the cap being thus reduced at the bottom of the groove to insure that the outer portion of the cap will be torn away when the pressure of the fuel in the main passage of the nozzle reaches about 200 lbs. per sq. in. at which pressure the fuel will be ejected from the nozzle as a rod-like stream.

The cap 15 is preferably provided with a conical forward end 23 concentric with the nozzle 11 and the inner diameter thereof at its rear open end is preferably flared outwardly as indicated at 24 to facilitate positioning by sliding the cap over the O ring 22.

The flame cone 14 is secured to a shroud 25 covering the forward end of the flame thrower. The shroud 25 is provided with an opening 26 axially aligned with the nozzle 1! and is of large enough diameter to provide an annular space around the forward end of the flame cone 14 to provide for the flow of atmospheric air around the exterior of the flame cone to enter the cone through the back thereof to sustain the flame therein.

The opening 26 is closed while the flame thrower is not in use by a plug 27 of light material such as foam plastic and of a shape such that is expelled together with cap :15 by the impingement of the latter thereagainst when the fuel tank is put under pressure by the firing of the flame thrower.

The plug 27 is provided with a wide head 28 which is slightly tapered inwardly in the direction of the length of the plug so that it may be readily engaged in and disengaged from the opening 26. From the head 28 toward the inner end of the plug the diameter of the body thereof is reduced as shown to substantially that of the cap 15 and is of a length such as to be placed a short distance ahead of the cap. The rearward face 29 of the plug 27 is conically recessed similarly to the conical forward end of the cap 15. The rearward taper of the plug facilitates its passage through the opening 26.

Operation When the flame thrower furnished with a nozzle provided with closure means arranged according to this invention is to be put into use the liquid held in the tank is put under pressure by releasing pressure gas into a tank and the pressure therein will increase until the predetermined value is reached at which time the cap covering the nozzle will rupture around the weakened wall portion and the freed front end of the cap, which is initially guided for true axial movement by the skirt of the retaining ring, will be violently projected forwardly.

The forwardly moving cap engages almost immediately with the closure of the shroud, when the device is fitted with one, and the conical forward end of the cap engages with the recessed conical inner end of the shroud closure thus exerting an axially directed force thereon which forces the head of the shroud closure out of engagement with the periphery of the opening in the shroud and both closures are carried out of the shroud by the rod-like stream of liquid under pressure and fall away from said stream.

A preferred embodiment of the invention has been specifically described and shown by Way of illustration but not by way of limitation of the invention since vari ous modifications may be made in the described embodiment by those skilled in the art without departing from the scope of the invention as defined by the appended claims.

I claim:

1. Closure means for a nozzle adapted to emit a rodlike stream of liquid, comprising: a cylindrical end portion of said nozzle having a main axially arranged orifice in its forward end to emit said rod-like stream of liquid and a laterally arranged restricted orifice through which a portion of the liquid is bled off; a tubular cap closure having a peripheral groove in the wall thereof adjacent the open end of the cap to weaken said wall; said cap having an outwardly projecting rim flange at its open end; and a clamping ring having a tubular forwardly extending portion surrounding said cap in closely spaced relation thereto, said clamping rim having an inner peripheral shoulder engaging against the rim flange of the cap, and said clamping ring having a rearwardly projecting internally threaded portion engaging with a threaded cylindrical portion of said nozzle.

2. Closure means for a nozzle adapted to emit a rodlike stream of liquid and for an opening in a shroud covering but spaced from said nozzle, the nozzle and shroud I openings being aligned, comprising: a cylindrical end portion of said nozzle having a main axially arranged orifice in the forward end thereof to emit said stream of liquid, and a laterally arranged restricted orifice through which a portion of the liquid is bled off; a tubular cap said clamping ring engaging with a threaded cylindrical portion of said nozzle; and closure means fitting in said shroud opening.

3. Closure means as set forth in claim 2 and in which the closure means for the shroud opening is formed with a head portion and an inwardly tapered stem portion extending rearwardly into proximity to the forward end of the closure mounted on the nozzle, the rearward end of the stem being inwardly recessed and the forward end of the tubular cap closure being formed to fit into the recessed end of the stem of the shroud closure.

4. A closure comprising: a nozzle adapted for emitting a pressurized fluid through a passageway, a hollow truncated cone-shaped housing open at each end and axially positioned on the longitudinal axis of said nozzle, a shroud surrounding said cone-shaped housing and having an opening axially aligned with said nozzle and said cone-shaped housing, a plug member in sealing engagement with said shroud opening and said cone-shaped housing opening, and a cap member means in sealing engagement with said nozzle and covering said nozzle passageway.

5. A closure as defined in claim 4 in which said cap member means has a weakened portion thereon whereby said pressurized fluid can sever said weakened portion and expose said nozzle passageway.

6. A fluid sealing device having in combination: a nozzle means for emitting pressurized fluids, a means for capping said nozzle means, a means for housing said nozzle means, a means for shrouding said means for housing and said nozzle means, said shrouding means and said housing means having passageways therethrough aligned with said nozzle means, a means for plugging said shrouding means and said housing means, and said capping means being capable of being forced from said nozzle means and thereby forcing said plugging means from said shrouding means and said housing means.

7. A fluid sealing device as defined in claim 6 in which the capping means is in sealing engagement with said.

nozzle means and has a weakened portion surrounding said capping means that is capable of being severed.

8. A fluid sealing device as defined in claim 6 in which the capping means has a conical portion having an axis concentric with said nozzle axis, said plugging means having a conical-shaped cavity substantially mating with said conical portion of said capping means whereby the capping means directs the plugging means externally of the housing.

References Cited in the file of this patent UNITED STATES PATENTS 926,075 Read et a1. June 22, 1909 1,327,190 Bigoney Jan. 6, 1920 1,593,025 MacDonald July 20, 1926 1,730,202 Geyer Oct. 1, 1929 2,025,782 Seat Dec. 31, 1935 2,327,528. Kendall et al. Aug. 24, 1943 2,338,094 Calleson et al. J an. 4, 1944 2,776,623 Bonner Jan. 8, 1957 FOREIGN PATENTS 1,159,192 France Feb. 10, 1958 

